foo.c: In function 'main':
foo.c:7:13: error: 'new' undeclared (first use in this function)
    7 |     int *gr=new int[n];
      |             ^~~
foo.c:7:13: note: each undeclared identifier is reported only once for each function it appears in
foo.c:7:17: error: expected ',' or ';' before 'int'
    7 |     int *gr=new int[n];
      |                 ^~~

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